Computers are often used for making presentations to one or more people. Business persons frequently travel to locations remote from their own office to meet with others taking with them only a laptop computer. Also, business persons often make presentations within their own working environment or offices. These meetings may be informal and entail only a presenter sharing computer information with a small audience of one or more individuals. These meetings may also be more formal and entail one or more presenters sharing information stored in a computer with a relatively large audience.
Information stored in a computer is sometimes of great value in making a presentation but difficult to share with an audience because the computer screen may not be visible and accessible to the audience. When the computer screen is positioned so that the audience can see it, the presenter is normally positioned behind or next to the screen where the image is either not visible or visible upside down or at a very sharp angle with respect to the presenter. The presentation is therefore limited by the type, orientation and size of display screen connected to the computer and the size of the audience.
There are a number of display products available which permit a computer to be used for presenting information to an audience. Laptop computers are available with a removable panel on the back of the computer screen. When the panel is removed, the screen, which is now transparent, may be folded down away from and parallel with the keyboard and set over an overhead projector screen. The image displayed on the computer screen will then be projected onto a wall or retractable screen in a conventional manner. This type of system requires access to a screen or a white and relatively smooth wall and also requires availability and use of an overhead projector.
An additional prior art product is available which projects an image received from a video output device such as a cam-corder or VCR onto a large screen or wall. The product includes a small liquid crystal display (LCD) screen which produces a video image and projects it onto a larger screen or a wall.
Another prior art display screen is a portable LCD projector having a housing which contains projection and light mechanisms inside. A rear projection screen is pivotally attached to the housing which when pivoted up to an essentially vertical position displays an image which is projected onto the screen from within the housing. This type of display only has one display surface which may be directed towards an audience or the presenter, but not both.
Another type of LCD projection system has a cylindrical rear projection screen which displays an image on the external surface of the screen. The cylindrical screen is rotated at a relatively high rate synchronized with an image periodically projected onto portions of the screen such that a viewer will see the image when it is projected onto the screen section normal to his or her angle of view. The rotation speed of the screen is such that viewers positioned around the screen will see a particular image substantially simultaneously. This type of display screen is relatively complex in construction and therefore somewhat costly and is not easily transportable since it is not collapsible.
One significant problem with these prior art devices is that a projected image does not have the same quality as the true original image. This is because a projected image is enlarged causing the image to have a lesser quality, fidelity and resolution when compared to the original displayed image. Another cause is that the image is often projected onto a surface such as a wall which is usually not clean, smooth and free of obstructions such as light switches, signs, artwork and the like.
What is needed is an improved presentation display device which displays an image visible simultaneously to viewers situated on opposite sides of the display device. What is further needed is a presentation display device which may be connected directly to a standard port of a computer for communicating therewith. What is additionally needed is a presentation display device which is highly portable and consumes a minimal amount of power. What is also needed is a presentation display device which is relatively simple in construction requiring little or no maintenance and is of relatively low cost. What is further needed is a presentation display device which produces an image visible in its original form and not in a from projected from a source to another surface or display medium.